中文摘要：

为探讨松树感染松材线虫后超氧自由基（O2.-）动态变化与寄主组织病变的关系,对黑松、马尾松和火炬松与松材线虫互作中的O2.-、超氧化物歧化酶（SOD）及组织病理学变化进行了研究。结果表明,3种松树在接种早期（接种后4 h）O2.-含量增幅和SOD活性大小依次为：火炬松、马尾松、黑松,且抗性松树上升幅度大,抗性松树受害较感病松树轻;至接种后期（接种后72 h至120 h）3种松树体内O 2.-含量和SOD活性从高到低依次为：火炬松、马尾松、黑松,火炬松病程发展较黑松和马尾松慢（马尾松慢于黑松）,受害轻。这表明不同抗性松树感染松材线虫后其体内O 2.-和SOD酶活变化与寄主组织病变密切相关,超氧自由基可能是松树受松材线虫侵染后介导抗病信号转导的重要信号物质。

英文摘要：

To explore the relationship between dynamic changes of superoxide anion（O-·2） in the pine trees infected by Bursaphelenchus xylophilus and the host tissue lesions,O-·2,superoxide dismutase（SOD） and physiological changes in the interaction between Pinus taeda,P.massoniana,P.thunbergii and Bursaphelenchus xylophilus were studied.The results showed that growth rate of O-·2 content and value of SOD activity in three kinds of pine trees was P.taeda P.massonianaP.thunbergii.At the early stage of inoculation（after 4 hours of inoculation）,it increased fast in the resistant pines.The damage of resistant pines was lighter than that of the susceptible pines;At the late stage of inoculation（after inoculation 72 h to 120 h hours）,the content of O-·2 and value of SOD activity in three pines was P.taeda P.massonianaP.thunbergii,the development of physiological changes of P.taeda was slower than that of P.thunbergii and P.massoniana（P.massoniana slower than P.thunbergii）,and the damage of that of P.taeda was lighter than P.thunbergii and P.massoniana.This indicated that the changes of O-·2 and SOD activity of in different resistance pines infected by Bursaphelenchus xylophilus were closely related to the host tissue lesions,superoxide may be important signal substances which mediated the resistant signal transduction in pines infected by Bursaphelenchus xylophilus.